Objective To explore the secondary metabolite profiles of Chimonanthus praecox from its main production areas, identify and analyze the variations in these metabolites and their metabolic pathways in Chimonanthus praecox from Yanling, Henan, and Beibei, Chongqing for providing a theoretical basis for the scientific cultivation of Chimonanthus praecox.

Method Extensive targeted metabolomics based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), metabolomic analysis was used to conduct on samples during the blooming period from two regions.

Result 1) A total of 2 175 secondary metabolites were identified in the samples from the two origins, which were mainly classified into 13 categories according to their chemical structures. Flavonoids were the most predominant with 387 types, followed by phenolic acids, lipids, alkaloids, terpenes, amino acids and their derivatives, lignans and coumarins, organic acids, nucleotides and derivatives, quinones, tannins, and steroids. 2）Compared with Chongqing Chimonanthus praecox, Henan Chimonanthus praecox exhibited 613 significantly different metabolites, of which 346 metabolites were significantly upregulated. This included 79 phenolic acids, 52 flavonoids, 38 alkaloids, 32 organic acids, 27 amino acids and their derivatives, 24 terpenoids, 8 lipids, 7 quinones, 7 nucleotides and their derivatives, and 38 others. 3) According to KEGG annotation, 129 differential metabolites were annotated across 83 metabolic pathways. Metabolites associated with the phenylpropanoid biosynthesis, flavonoid biosynthesis, amino acid biosynthesis, and ABC transporter pathways were notably enriched. Significant enrichment was observed in five metabolic pathways: phenylpropanoid biosynthesis, phenylalanine metabolism, diterpenoid biosynthesis, flavonoid compound biosynthesis, and the synthesis of ubiquinone and other terpenoid-quinones.

Conclusion A total of 2175 secondary metabolites were detected in Chimonanthus praecox from two main production areas. Chimonanthus praecox in the two areas showed significant differences in secondary metabolites, including 613 significantly different metabolisms, mainly concentrated in phenolic acids and flavonoids. Among them, Eucommia lipoid A and aescin are the key markers for distinguishing Chimonanthus praecox from the two main producing areas. There are many differential metabolites in phenylpropanoid biosynthesis, flavonoid biosynthesis, amino acid biosynthesis, ABC transporter and other pathways. The differential metabolites of phenylpropanoid biosynthesis, phenylalanine metabolism and diterpene biosynthesis are significantly enriched.